Hi there,
After pushing my latest code, I now get this error on resin:
Failed to download application ‘registry.resin.io/nameofapp/gittag’ due to ‘Failed to get image download size of 303b5307a77886b50c9e27ef0301fdb48b5d0xxxx from registry.resin.io. Status code: 400’

When you update your application, do you also require new dependencies to be installed? This usually has to do when trying to install new dependencies, but the installation is aborted. For instance, if you install dependencies via apt-get install, you can add ‘-y’ in order to assume “yes” when confirmation needed. Is this your case?